The attached patch provides base enabling for PowerPC Altivec (AKA VMX) 
and for versioning effected functions. 2.6.0 kernels provide a 
PPC_FEATURE_HAS_ALTIVEC status in the AT_HWCAP. We need to capture this 
status as a static flag (__has_altivec) so functions enabled for altivec 
can run safely on PowerPC hardware without the Altivec feature.

And now for the fun part. I think this requires a new glibc version 
because GLIBC_2.3.3 symbols are already defined for these 
(get/setcontext) functions in shipped distros.